feature film vs photoplay

feature film

noun
  • The main, full-length film in a cinema program that also included a short film and often a newsreel. As of now, it plays after the trailers. 

  • Any film produced to be shown in cinemas before being released for home viewing. 

photoplay

noun
  • A theatrical play that has been filmed for showing as a movie. 

  • A novel adapted from a movie and illustrated with photographic stills taken from the film. Usage largely confined to the silent era of Hollywood. 

How often have the words feature film and photoplay occurred in a corpus of books? (source: Google Ngram Viewer )